What Fuel

[Moehawkkid]

Ok thanks a lot you are helping out and I appreciate it What is funny is that I am
getting both (symptoms). Sometimes when I try it there is a big whoosh and then a small
flame near the hole. other times when I shake it up well A big flame comes out very
loudly and it does two cycles. It is 15 degrees Fahrenheit outside so that might mean
something. the smaller can is the one that has this problem I will play with a little
more but I will also open my bigger 46oz can and start out with a 3/8 inch hole and then
slower get to a bigger hole, until it runs well. I get my jars so run very well so well
in fact they crack. My first jar I tried started right up with no problems. I want to use
cans so they wont crack. I will try a can today inside and see if runs inside.

[Moehawkkid]

I got it to work. I used the 46 oz can started out with a 3/8 hole tried to light it and I flame shot out 1 foot and it was very loud. The top and bottom of the can were pushed out. The hole was much too small. Then I drilled a 1/2 hole in the can and the flame that shot out was smaller and a little less loud. The can made a few cycles. To make the hole even bigger I have to use a screwdriver and just push the sides of the can way to make it bigger. I then tried again and it worked. It ran for about 20 seconds then quit because it got hot. And to day a used some magnets to hold it down in a bucket of water and it will run for about 1 minute before it overheats. I can not belive how hot this can gets. I will try a smaller can so it does not get hot as fast and it will cool better in water. My engine does not run very fast, slower than I thought it would. About one cycle every second. I also tried to run it on denatured alcohol and it ran for longer and a littel faster than it did with Heet. I wonder why this is? I will not get another 26 oz can try to make it run again but start out with smaller holes then work my way up until it runs.

I am very happy with this. After a week a got one to run.

[Moehawkkid]

I found this and it talks about all differnt kinds of fuels for stoves and possibly for me my engines. It says

"The vaporization pressures of methanol are much higher than ethanol throughout the applicable temperature ranges and the jets in your stove might light up faster when using this fuel."

That explains why it gets hotter running on methanol but not why it runs longer and faster than on denatured alcohol. I am still happy that I got it to run though. I will post a video on youtube talking about how I made it and a video of it running. Hopefully it will help mre people to make one.

http://zenstoves.net/Stoves.htm

[PyroJoe]

A minute run is good, especially for this being your first week at it. Ethanol alcohol has a slightly higher energy density than methanol alcohol, which may explain the difference.

If you like a faster running engine, the smaller engines tend to cycle faster. If you put a small metalic tray in the bottom of the glass jars, and only place the fuel in the tray. They will tend to have less thermal shock and are less likely to crack.
Joe

[Moehawkkid]

Here is a video. When this is using denatured alcohol it not only runs faster but longer. With Heet there still is fuel when it goes out. I have some other runs in other videos when it only stops when it runs out of fuel. I am very happy with it. In this video luckily no water got in the can. What do you think?

http://www.youtube.com/watch?v=Melo332U ... annel_page

[PyroJoe]

Good job! That first whoosh is a duck and cover, then she settles into a healthy cycle. Goes on to run for nearly two minutes. Very cool. ha
Joe

[Moehawkkid]

Two things.

1. When not using Heet it takes longer to start. I had to try it 5 times before it worked.
2. It runs so much longer than it does on Heet. Even when it is cooled it would only run for 40 seconds or so. Then when I tried alcohol it runs better and longer. When I ran it before it stopped only when it was out of fuel. In the video the run was cut short but it made for a good ending.

[phonedzero]

Great run wtg!

[GRIM]

That Is one of the best "can" runs I have ever seen , well done ,

[Moehawkkid]

Thank you very much.
I should post a video of it running without problems. It might get kinda boring though because it will run until it it runs out of fuel.

[Mark]

Not a bad run. What kind of magnet are you using to hold your can down and is it inside the larger can or outside, just out of curiousity? It may be fortunate that you decided to use a magnet, for it might prevent the bottom of your can flexing out of sync with the top. I'm not sure about this effect, but it is a variable that comes to mind.
What kind of denatured alcohol are you using, I'm trying to pin down what ingredients are in it and the ratios. Could you post a picture of the denatured alcohol bottle or find one in Google pictures if you type the product's name?
Perhaps you could try a short run with the can out of the water, this would help determine if the flexing or stiffness of the bottom is critical. Or I guess you could hold the can down by other means in the water and see if she still likes to run, if you wanted to that is.
I've had a little chrome plated brass syringe run for over 5 minutes submerged in a gallon coffee can full of water. I had to fight the steam that formed, by drawing it away with the back of a fan. I think overall the larger the vessel, the less fussy the fueling. Like those little pulsejets, they run on acetylene or hydrogen, fuels that run way rich or lean.
I have used 190 proof Everclear with some of my jam jars, but at $35.00 a bottle, it was frivolous.

If you can imagine unscrewing the tip/needle and the bottom of this syringe mounted to an aluminum disk, that was the arrangement in my coffee can of water.
http://www.istockphoto.com/file_thumbvi ... yringe.jpg

[Moehawkkid]

Thank you
Now the questions

1. I am using magnets that are used for model slot cars. My guess is that they are neodymium magnets because they are vey strong. I am using 4 magnets and they are only 1/8 inch wide by 1/2 inch long. Very strong. I am thinking about buying some magnets from this place. Or just any other good source of neodymium magnets. I have bought stuff from them in the past and it was very good service.

http://unitednuclear.com/magnets.htm

2. The Denatured alcohol is what I had just around the store. We use it for cleaning models and stripping paint. Here is the brand I used

http://paint-and-supplies.hardwarestore ... 05435.aspx

Today I went to a hardware store to buy some more alcohol, they did not have the brand I used before and I just got another one that said Denatured alcohol solvent. Worked just as well. Both cans say they can be used for marine fuel. My guess is that any Denatured alcohol that says that will work.

3. My can will only run out of water for 20 seconds then it quits. It is also much harder to start it out of water which is very funny. My dad suggested it may act like some sort of shock suppressant. To back this theory up my can runs differently depending on what bucket it is in. The video bucket was almost completely circular and I ran the can in another bucket. An oval shaped one and the can runs faster and louder. The oval bucket is larger. I would like to investigate this more.

4. The bottom of my can is bowed out. It did this not during normal run but when I was testing the size of the hole to use. I had a hole that was too small and when I lit the can it bowed out both sides of the can.

There are so many variables that affect this. I will definitely look into making a better running can.

One more interesting blip. I don't know if this happens to others but when I try to light the can and fail a small flame burns right at the hole and the cool part is that the can "sings" it emits a soft hum. It is very cool I will try to record this.

[Mark]

The little tone is common to little jars as well, when they have been run and the air isn't fresh enough/too spent for the flame to climb down inside the jar. I had it happen on an 8 inch diameter steel gazing ball that I drilled a hole in. The dome of fire made a nice hum for some time.
Another time I made a foot long pulsejet with a single petal valve. When I primed the tailpipe, it would sometimes hum for several seconds just like your description and then the flame would decide to advance and the jet would roar to life. That was a funny effect that really tickled me.
Thanks for your information and posting a reply. Good luck in your adventures too!

[Mark]

In looking at your S-L-X Denatured Alcohol I see that 45-50% is "ethanol". ** "Above ingredient consists of the following."
85-90% ethanol, methanol 1-4%, methyl isobutyl ketone 1-5%.
Then the remainder, methanol is 45-50% if I read the MSDS chart correctly.
http://paint-and-supplies.hardwarestore ... 05435.aspx
http://www.hardwarestore.com/media/msds/605435.pdf
(Also in section 3, (continued page) of the above link it states the upper limit by weight for methanol in this product is 52%)

That chart jives with this chart I dug up earlier. Kind of a 50/50 blend of the two alcohols for the most part, for this particular product . (See 2. Composition/Information on Ingredients)
http://www.brown.edu/Departments/Visual ... lcohol.pdf

[Mark]

One other thing, if you are going to be jam jarring often, it is best an outdoor experiment. The fumes of those incompletely burned chemicals can be noxious. No telling how all three might interact either. Perhaps you can detect some formaldehyde.
And neo magnets will chip the protective nickel coating occasionally and then react with the air so you should wash your hands after handling them. And don't let them get too hot either. ha
"Neodymium magnets should never be heated above 175 o F or 80o C as they will loose their magnetic properties. In addition, they may catch fire and burn and produce toxic fumes."
"Thus, Neodymium magnets have many industrial, education and household uses but only when handled with extreme care and precaution."
http://www.whatareneodymiummagnets.com/safety.html